A large portion of the blue collar work force in Delhi and the National Capital Region (NCR) are migrants from other mainly poorer states. Many live in illegal slum colonies and find it difficult to gain access to bank accounts making it difficult for them to save and attain financial security.
To get around this problem, people get together in groups and create their own kitties where they contribute cash they can spare. Usually these groups are based on clan or community affiliations as these linkages inspire trust between the members. The corpus built up over time is used to support the members' requirements related to education, health etc. Trust and empathy are the most important factors for this kind of arrangement to work. Such groups are created around one person who has been a resident in the city for a long time and has managed to gain access to a bank account.
There are also some organisations who help low income people get their own bank accounts. A really great example is The Maids Company (http://www.themaidscompany.com/). The Maids Company has tried to formalise the largely unregulated market for domestic help in India. Apart from ensuring that such workers get paid fair wages by the hour, the company also helps them open bank accounts, get their verifications done by the local authorities, get them enrolled in the national register to access subsidies provided by the Government. This has helped hundreds of destitute women gain financial independence, educate their children and live a dignified life.